Trace Elements in West Virginia Coals

Hafnium (Hf)

Highest
hafnium contents (3.0-7.2 ppm) were in the upper Kanawha Formation coals
of Boone and Logan counties, and intermediate hafnium contents were confined
to coals of the southern coalfield. Coals with the lowest (<1
ppm) hafnium content were distributed statewide, with all northern coalfield
coals are low in hafnium.